Cornflower

In short: Cornflowers need a sunny to semi-shaded spot and well-drained, nutrient-rich soil with calcium. Sow from March to April, once temperatures reach at least 10 °C, in rows 25 to 30 cm apart. Pre-grown large-headed cornflowers are moved to their final place from May to July at 50x50 cm spacing.

The brilliantly blue cornflowers can often be seen in fields and meadows, but why not have them as decorations in our gardens as well. They can be grown as annuals or as perennials, with annuals being smaller than perennials and spreading more slowly.

In addition to classic blue cornflowers, you can also grow white, yellow, pink or purple varieties in your garden.

Cultivation

Since the cornflower is very undemanding, even a complete beginner can grow it. For growth, it needs a sunny or semi-shaded location and well-drained soil with plenty of nutrients and calcium.

Cornflowers do not require fertilization, but you certainly won't harm them by doing so.

Start sowing in March or April, when temperatures reach at least 10°C. Sow the plants in rows that are about 25 to 30 cm apart.

If you want to pre-grow cornflowers, choose the large-headed cornflower. In this case, the seeds are sown in seed trays from March to April. The plants are then transplanted to their final location in May to July with a spacing of 50x50 cm.

Types

Perennials

• Mountain Cornflower (Centaurea montana) - this cornflower is protected by law, the edges of its flowers have a blue colour and purple in the centre. Don't be afraid to cut it back, it will bloom again soon after.

• Persian Cornflower (Centaurea dealbata) - its flowers have a purple colour, which is beautifully carmine towards the centre of the flower

• Giant Knapweed (Centaurea macrocephala) - has large yellow flowers, which we can see in the first year of cultivation, giant knapweed tolerates even drier clay-sandy soils

• Greater Knapweed (Centaurea scabiosa) - we can see it growing in light forests, on slopes or meadows, it boasts purple flowers and thrives in alkaline to neutral drier soils

• Brown Knapweed (Centaurea jacea) - this cornflower thrives in clay soils, we can see it freely in clearings, roadsides or field boundaries, the flowers also have a purple colour

Annuals

• Cornflower (Centaurea cyanus) - also known as bachelor's button, it is an annual or possibly biennial plant, which we recognize by its typical blue colour

• Sweet Sultan (Centaurea moschata) - with this cornflower we can most often see bright yellow flowers, but varieties blooming in pink-purple or other colours can also be found

• Imperial Cornflower (Centaurea imperialis) - imperial cornflower has massive flowers that can decorate our garden in various colours

Cornflowers are wonderful for cutting and for dried flower decorations